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3#
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發表於 2008-5-18 17:13:16
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恩~是的~我是要把它除到1HZ因為實驗器材的內部震盪晶體為40MHZ$ A+ I2 N# F) Y* ~& ]: o, y( O- s
除完1HZ接上計數器這樣~下面是我後來又改的><" 難道精準式除頻有很多種方法做??
7 M+ A& u3 D9 hentity clk_95 is
7 c. Q: ^+ S/ [# ^, v Port ( clk40 : in STD_LOGIC;1 a) a% P$ ^5 Z) |/ R& y7 X5 J
enable : in STD_LOGIC;9 ~% }; M& P' g! J" C# U
switch : in STD_LOGIC;6 F( i6 m) c: @% c" P! |
a,b,c,d,e,f,g,p : out STD_LOGIC;
. ]- y* H/ y" |! @3 u SEL : OUT STD_LOGIC_VECTOR (5 DOWNTO 0));
* ^& }# ~7 S9 m/ [end clk_95;
0 f& n) b" r) K5 Y7 U% ]
! e, @5 J- G, U" i! b# n4 B+ K, d" barchitecture Behavioral of clk_95 is: A( \8 S& Y# n6 S
signal clk1 : STD_LOGIC ;
- {* D: B. v: k4 Wsignal cnt : STD_LOGIC ;1 G# c! q7 B; C, y! D
signal x1 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);. y* p5 ^. H7 m( i
signal x2 : STD_LOGIC_VECTOR ( 3 DOWNTO 0);+ ]/ T0 ~( y8 D3 @7 W
signal count1 : STD_LOGIC_VECTOR (3 DOWNTO 0);
- I, ~3 c* i6 e& Dsignal count2 : STD_LOGIC_VECTOR (3 DOWNTO 0);3 w3 s# A; G$ ?) c) _' o
signal y : STD_LOGIC_VECTOR (7 DOWNTO 0);
2 h7 ]; \. k0 ebegin
2 ]/ H- Y/ l; M4 ^( w3 F P
Q7 D8 T( A0 I# Z5 C process(clk40)0 H" X/ `" L7 k! A( z. F- z
variable cnt:integer range 0 to 39999999;$ V8 l/ X/ x5 \ Y9 |" T7 J
begin
4 A6 Q, \' {! t if clk40'event and clk40='1' then
0 k. }0 N% Y/ a- F* y' f if cnt<20000000 then* u& h( D+ b+ H7 x1 W) u
cnt:= 0 ;
1 o) b+ r0 V3 W else
( Q6 G7 F; q0 }, W! d; r cnt:= 1 ;
5 V% M8 ^8 D. q1 O, A* K1 w7 ` end if;8 l% W4 Z, K' r2 x. Q
end if;
0 U/ \ |/ i0 T; R end process;
2 K6 _2 L! ] d- B- b: ^4 y clk1<=cnt;
+ ^# ~# E4 a8 J0 Q6 t: g! O+ m* ^
/ K8 _2 b: x, }( K) m' @ process(clk1)% ]6 o8 j8 A1 @/ |
begin- u( N4 P* z4 F W
if clk1'event and clk1='1' then' @/ o3 r! }5 Q' U9 L
if switch='0' then/ d3 q, k7 W6 @7 r L; C7 I
count1<=count1 + 1 ;4 @, d3 X; Z3 @7 w
if count1="0110" then$ j L8 m; a) g5 B% |2 J
count1<="0000" ;
6 @' [/ R* a3 m0 U6 @& ]! W end if;
, I( e1 v' { A6 ^" B7 A* u& B7 X else( s& n& r* @) @4 N. O# y7 h; y: J
count2<=count2 + 1;
' d2 w6 L, R B0 N5 o( q2 H if count2="1000" then2 U+ X1 |- H! g
count2<="0000" ;
9 v" C8 p( y' }& W6 @3 u4 i end if;/ [. ]. h2 i( z; ~$ k
end if;
6 f1 M$ \3 P# y& N! f* Z" Q end if;
( y) w/ [! V" v- C! w* V6 M$ J* u end process;
r, ?/ R9 d, Y7 \- l4 I後面是我自己要接出去的東西~所以我沒PO!! |
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